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Members of the genus Sarcocystis (Apicomplexa: Sarcocystidae) are intracellular protozoan parasites that infect a wide range of domestic and wild animals, resulting in economic losses in production animals worldwide. Sarcocystis spp. have indirect life-cycles where canids and felids serve as main definitive hosts while a range of domestic and wild animals serve as intermediate hosts, including South American camelids (SACs) such as alpacas, llamas and guanacos. These animals primarily occur in South American countries on Andean, elevated plains but in recent years, alpacas and llamas have become emerging animal industries in other parts of the world such as Australia, Europe and the USA due to their high-quality fiber, meat and hides. For instance, alpaca meat is becoming popular in many parts of the world due to its lower cholesterol content than other red meat, thereby it has the potential of a valuable product for both local and international markets. However, SAC meat can be degraded and/or even condemned due to the presence of macroscopic sarcocysts in skeletal muscles, leading to significant economic losses to farmers. The infection is generally asymptomatic, though highly pathogenic or even fatal Sarcocystis infections have also been reported in alpacas and llamas. Despite the economic importance of sarcocystosis in SACs, little is known about the life-cycle of parasites involved, disease transmission, epidemiology, pathogenesis, diagnosis, control and public health significance. This review article provides an in-depth analysis of the existing knowledge on the taxonomy, epidemiology, clinicopathology and diagnosis of Sarcocystis in SACs, highlights knowledge gaps and proposes future areas of research that could contribute to our better understanding of sarcocystosis in these animals.

Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites)., (Copyright © 2014. Published by Elsevier Ltd.)

Cryptosporidium is an important enteric parasite that is transmitted via the fecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Most species of Cryptosporidium are morphologically indistinguishable and can only be identified using molecular tools. Over 24 species have been identified and of these, 7 Cryptosporidium species/genotypes are responsible for most human cryptosporidiosis cases. In Australia, relatively few genotyping studies have been conducted. Six Cryptosporidium species (C. hominis, C. parvum, C. meleagridis, C. fayeri, C. andersoni and C. bovis) have been identified in humans in Australia. However, little is known about the contribution of animal hosts to human pathogenic strains of Cryptosporidium in drinking water catchments. In this review, we focus on the available genotyping data for native, feral and domestic animals inhabiting drinking water catchments in Australia to provide an improved understanding of the public health implications and to identify key research gaps.

Neospora caninum is transmitted either transplacentally or horizontally by ingestion of tissue cysts present in tissues or oocysts shed by dogs. Neosporosis is a significant disease, causing cattle abortion at 5-7 months of pregnancy. Infected cows may remain infective for life transmitting the infection in several consecutive or non-consecutive pregnancies. A great deal is known about the epidemiology of neosporosis, although only limited information is available on the main routes of horizontal transmission. In Australia, the presence of the dingo as the top-order predator suggests a potential sylvatic route of transmission between dingoes and as yet unknown native wildlife in addition to the domestic route via dogs with access to infected tissue on farms. This review article critically evaluates the overlap between the domestic and sylvatic routes, taking into account canine ecology, and summarises current understanding of the transmission of N. caninum to provide a foundation for epidemiologists, farmers and conservation biologists dealing with neosporosis and wild dog control programs., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Echinococcus granulosus is the only member of the Genus Echinococcus to occur in Australia. The major biomass of E. granulosus occurs in wildlife. The wildlife transmission cycle is predominantly perpetuated via a predator/prey interaction between wild dogs (dingoes and dingo/domestic dog hybrids) and macropodid marsupials (wallabies and kangaroos). Other wildlife hosts include foxes, wombats and feral pigs. This wildlife reservoir for E. granulosus "spills over" to help maintain a domestic cycle through E. granulosus-infected wild dogs defecating on pasture, transmitting infection to livestock and some farmers and hunters feeding hydatid-infected offal of macropodids or feral pigs to domestic dogs. The potential transmission risk to humans using public picnic and camping areas in parks and forests, especially in the southeastern Australia, could be substantially reduced through regular distribution of baits containing praziquantel. Encroachment of wild dogs and foxes into urban centers presents a new potential path of transmission from wildlife to humans.

A combined immunomagnetic separation (IMS) and flow cytometry (FC) technique was developed for the sensitive detection of Cryptosporidium in faecal samples. The IMS/FC technique was found to be approximately 50-fold more sensitive than formol-ether concentration, which is commonly used for Cryptosporidium epidemiological investigations. Of 31 faecal samples from captive animals 16 were found to contain Cryptosporidium oocysts when analysed using the IMS/FC compared to four when using formol-ether concentration (FEC). In a wild population of eastern grey kangaroos Macropus giganteus 66.3% of infected animals were shedding <500oocysts/gfaeces when analysed using IMS/FC. This is below the detection limit for the FEC method. The dispersal of Cryptosporidium in host populations is aggregated, with many individuals shedding low numbers of oocysts and few individuals shedding numbers of oocysts sufficiently high to be detected by FEC. This research demonstrates that the prevalence and oocyst shedding intensity of Cryptosporidium in animal populations will be significantly underestimated using standard detection methods.

Ancylostomatoidea or hookworms recorded in Australia are reviewed and the attempt is made to provide the biogeographical background to their occurrence. The poor representation of this nematode superfamily is probably a reflection of the fact that they are primarily parasites of Carnivora, Artiodactyla, Insectivora, Rodentia, Edentata, Proboscoidea and primates, eutherian mammals which are either absent from the Australian fauna or which have only recently reached the continent. The principal genera of hookworms recorded to date from Australia are Ancylostoma, Bunostomum, Necator and Uncinaria. The majority of the ancylostomatoid fauna is represented by introduced species of man and domestic animals. Native or endemic species of hookworms are restricted to members of the genus Uncinaria with two species occurring in rodents and pinnipeds. Only a single endemic species of hookworm is known, U. hydromyidis, which is found in the small intestine of a rat. Significant problems remain in understanding the systematics, epidemiology and evolutionary relationships of the Australian ancylostomatoid fauna.

Animal trypanosomosis caused by Trypanosoma evansi is endemic throughout Southeast Asia, where it is an important constraint on the productivity of smallholder livestock. In the past decade, T. evansi has emerged as a serious threat to the viability of smallholder livestock industries in the Philippines and causes severe disease outbreaks with high mortality. Trypanosoma evansi also poses a threat to livestock and native fauna in Australia and Papua New Guinea (PNG) where it is absent, but the risk of it spreading from Indonesia is high. Surveillance for T. evansi in PNG and Australia, and its control in the Philippines is restricted by the poor sensitivity and inadequate validation of existing diagnostic tests and lack of information on the determinants of infection.

The Australian cestode fauna remains poorly documented with a total of 342 species recorded to date. The best-studied host groups are the elasmobranchs and the marsupials, but even in these groups, only 32 and 25% of known host species, respectively, have been examined for parasites. Overall, cestodes have been reported from only 5% of the known vertebrate species. Representatives of virtually all cestode orders and most of the cyclophyllidean families have been recorded from Australia. In spite of these deficiencies, some biogeographical patterns are discernible. In the elasmobranchs, a significant proportion of the known cestodes is endemic while other associations exist with eastern Pacific and Indo-west Pacific faunas. Also identifiable is a group of cosmopolitan species. The nematotaeniids of amphibians suggest Gondwanan affiliations, while the known proteocephalideans, parasitic in reptiles and amphibians, may represent an Asian invasion. Associations of the avian cestodes represent an unexplored but potentially rewarding avenue of biogeographical study. The cestodes of mammals include families with a Gondwanan distribution (Linstowiidae, Hymenolepididae) as well as those (Anoplocephalidae) with an apparent origin in southeast Asia. In addition, a number of genera of cyclophyllidean cestodes (Anoplotaenia, Dasyurotaenia) occurring in marsupials represent biogeographical challenges, not being accommodated within any of the known cestode families. The Australian cestode fauna therefore provides potentially outstanding opportunities for studies of the biogeographical relationships of a number of cestode groups.

Indonesia and Australia are close neighbours sharing agro-ecological zones and common parasitological interests. Australia is an industrialised country and Indonesia is both industrialising and a developing country. The types of collaboration, contractual, collegiate, research collaboration and partnerships are briefly described. All forms of collaboration have and continue to exist between Australia and Indonesia. A survey of mammalian parasitology publications over the last 23 years indicates that the bulk of papers have been by Indonesian and non-Australian authors. Australian and Indonesian authors provided 4% of the total number of publications. The rational for collaboration is suggested to be the high degree of common multiple interests and the synergy of effort that can be derived from research partnerships. The most difficult issues in research collaboration are establishing the research priorities and, to a lesser extent, funding. The globalisation of the international research centre, International Livestock Research Institute, to include Asia will expand the opportunities for research collaboration. Details of the Australian Centre for International Agricultural Research mandate in supporting parasitology research collaboration is briefly described. The past and current research collaborative activities are reviewed and opportunities for future collaboration are listed.

A cost-benefit model is developed to estimate the costs of major parasites to Australian livestock industries and to evaluate the benefits from improving parasite management. The model disaggregates the Australian livestock industries into agro-climatic regions and various stock classes to estimate the total treatment and production loss costs of major parasites. Experimental trials and a computer simulation model are used to estimate the productivity of livestock under different treatment regimes. Using the model, the economic costs inflicted by cattle ticks, sheep gastrointestinal worms, sheep lice and sheep blowflies are discussed and the farm profitability resulting from improved sheep roundworm management is assessed.

Enzyme electrophoresis was used to examine genetic variation within and between populations of Echinococcus granulosus from domestic and sylvatic hosts in western and eastern Australia. Substantial genetic diversity was found within all populations. There was no evidence, however, of genetic differentiation between populations from different hosts or geographic areas. When isolates were grouped into previously described domestic or sylvatic strains on the basis of rostellar hook morphology, most (94%) of the genetic variation occurred within, rather than between strains. These results conflict with the currently accepted theory of separate domestic and sylvatic strains of E. granulosus on the mainland of Australia.